Dabigatran etexilate for preventing stroke and systemic embolism in atrial fibrillation

摘要

Atrial fibrillation causes embolic stroke when thrombus formed in the nonfunctioning left atrial appendage detaches and lodges in a cerebral artery. The prevalence of atrial fibrillation rises with age, from less than 0.1% in people younger than 55 years to more than 10% in those older than 80 years. Atrial fibrillation accounts for 7% of ischaemic strokes in people aged between 50 and 59 years, rising to one-third in octogenarians. Embolic strokes are often severe, and 15 to 30% of survivors are left permanently disabled.Antithrombotic therapy is effective.1'2 The vitamin K antagonist warfarin prevents about 65% of strokes in patients with atrial fibrillation and has twice the effectiveness of aspirin and is more likely to prevent severe stroke (Table 1). However, warfarin causes more major bleeding: 2.2% per annum compared with 1.3% with aspirin. This makes it essential to balance effectiveness with safety when recommending treatment. Almost 85% of people with newly diagnosed atrial fibrillation are candidates for antithrombotic therapy to prevent stroke.